I Completed My Quiz But I Can't Continue

Problem:

I have completed my quiz, I click "save my answers", but I don't get the green checkmark indicating that I have completed the quiz.
 

Solution:

This probably means that there is one question that you have forgotten to answer. Please go through all questions again and be sure to provide an answer. We have two types of quiz questions, multiple choice (where you have to click one answer) or text (where you type your answer into a text box).
 
If a quiz is taking you a while to complete, please save your answers regularly to prevent loosing your work. You can click "save answers" at the bottom of the quiz.